Grey H M, Abel C A, Yount W J, Kunkel H G
J Exp Med. 1968 Dec 1;128(6):1223-36. doi: 10.1084/jem.128.6.1223.
The gammaA2-subgroup of gammaA-globulins, previously delineated by antigenic studies, was found to differ strikingly from other immunoglobulins in the manner in which the polypeptide chains are bound together. The heavy and light chains were not linked to each other by disulfide bonds. Instead the light chains were disulfide linked to one another, and were present in the gammaA2-molecule as disulfide bridged L-L dimers. Antisera specific for gammaA2-proteins indicated the occurrence of two different antigenic types in all normal sera as well as saliva and colostrum. Both of these showed the unique interchain disulfide linkage. Quantitative analyses indicated higher levels of gammaA2-proteins in external secretions.
先前通过抗原研究界定的γA球蛋白的γA2亚组，在多肽链结合在一起的方式上被发现与其他免疫球蛋白有显著差异。重链和轻链不是通过二硫键相互连接的。相反，轻链通过二硫键彼此相连，并以二硫键桥接的L-L二聚体形式存在于γA2分子中。针对γA2蛋白的抗血清表明，在所有正常血清以及唾液和初乳中都存在两种不同的抗原类型。这两种类型都显示出独特的链间二硫键连接。定量分析表明，外分泌液中γA2蛋白的水平较高。
